Solvent systems for dicyandiamide and/or alkyl thiophosphoric triamide and use in agricultural applications

ABSTRACT

An inhibitor composition contains dicyandiamide as a nitrification inhibitor, alkyl thiophosphoric triamide as a urease inhibitor, or a combination thereof, dissolved in a liquid medium comprising an organic solvent selected from, among others, one or more polar aprotic solvents, including one or more organophosphates, amine solvents, heterocyclic alcohol solvents, and mixtures thereof, is useful in making fertilizer compositions and in a method of fertilizing target plants.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 62/066,513 filed Oct. 21, 2014, incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

This invention relates to liquid compositions comprising dicyandiamideand/or an alkyl thiophosphoric triamide, methods for incorporating suchcompositions with agricultural fertilizer compositions, agriculturalfertilizer compositions comprising dicyandiamide and/or an alkylthiophosphoric triamide, and the use of such compositions.

BACKGROUND OF THE INVENTION

In the agrochemical industry, farmers use various fertilizers to impartmacronutrients to plants either by application to the soil orapplication to plant leaves. Nitrogen, phosphorus, potassium, calcium,magnesium, and sulfur are macronutrients that must be supplied to theplants and soil manually by farmers. In many crops, the amount ofnitrogen supplied is critical to the overall quality and growth of thecrop. Nitrogen is typically supplied in the form of nitrogenous, i.e.,nitrogen precursor-containing, fertilizer compounds, such as urea,ammonium nitrate, or ammonium phosphate fertilizer compounds. Due to thehigh water solubility of these salts, however, applied nitrogen valuesmay be lost due to run-off and leaching of the nitrogenous fertilizercompounds. Once applied, the nitrogenous fertilizer compounds aretypically degraded, for example, by microorganisms present in the soil,to nitrogenous species such as NH₄ ⁺, NO₂ ⁻, NO₃ ⁻, and ammonia gas,that may be even more readily lost through evaporation, run-off, andleaching than the fertilizer compounds themselves. If degradation of thefertilizer compounds occurs at a rate that is faster than thenitrogenous degradation products can be used by the plants, then thenitrogen values in the degradation products are at increased risk ofbeing lost.

Nitrification and/or urease inhibitors are of potential use in delayingdegradation of fertilizer compounds and thereby reducing losses ofnitrogenous degradation products that would otherwise occurred in theabsence of the inhibitors. The use of nitrification and/or ureaseinhibitors in combination with nitrogenous fertilizer compounds tends toincrease the amount of time the nitrogen source remains in the soil andavailable for absorption by the plants, which tends to increase theeffectiveness of the fertilizer and positively impact crop yield andquality.

Aqueous end use fertilizer solutions are typically prepared in the fieldby diluting commercially available concentrated fertilizer compositionswith water. Commonly used concentrated fertilizer compositions includeconcentrated ammonium nitrate compositions, such as, for example, UAN18, UAN 28, UAN 30 and UAN 32.

Dicyandiamide is potentially useful as a nitrification inhibitor in suchaqueous end use fertilizer compositions, but has very low solubility(about 41 grams per liter (“g/l”) in water and so is difficult toincorporate into the aqueous end use fertilizer compositions,particularly under field conditions

SUMMARY OF THE INVENTION

Urease inhibitors can be used with a fertilizer (i.e., incorporated intoa urea-containing fertilizer, e.g., urea and urea ammonium nitrate(UAN)) to slow the conversion of ammonium to ammonia gas and thus slowthe loss of ammonia to volatilization, thus making ammonium available toplants in the soil for longer periods of time. In many crops, the amountof nitrogen supplied is critical to the overall quality and growth ofthe crop. Nitrogen is supplied in either urea or ammonium phosphateforms. Due to the high water solubility of these salts, however, much ofthe nitrogen applied is lost to run-off and leaching. In ammonium-basedproducts, if the nitrogen is not lost to leaching or run-off, it isbeing converted to ammonia gas by an enzyme called urease. Althoughammonia can bind to soil particles, conversion occurring near thesurface of the soil does not allow for binding and, thus, ammonia islost to the atmosphere. Urease inhibitors are used to protect a farmer'sinvestment in fertilizers by preventing the breakdown of urea by urease,the soil microbe responsible for converting urea to usable ammonia inthe soil. This increases the amount of time the nitrogen remains in thesoil and is available to the plant for absorption.

Similarly, nitrification inhibitors can be used with a fertilizer (i.e.,incorporated into a urea-containing fertilizer, e.g., urea and ureaammonium nitrate (UAN)) to slow the process of ammonium conversion tonitrate, and subsequently the loss of nitrate to leeching, thus makingammonium available to plants in the soil for longer periods of time.Ammonium is one of the main forms of nitrogen that can be utilized byplants. Increasing the amount of time that the nitrogen is available tothe plant increases the effectiveness of the fertilizer which positivelyimpacts crop yield and quality.

Fertilizers, in one embodiment, are common water soluble inorganicfertilizers that provide nutrients such as phosphorus-based,nitrogen-based, potassium-based or sulphur-based fertilizers. Examplesof such fertilizers include: for nitrogen as the nutrient: nitrates andor ammonium salts such as ammonium nitrate, including in combinationwith urea e.g. as Uram type materials, calcium ammonium nitrate,ammonium suphate nitrate, ammonium phosphates, particularlymono-ammonium phosphate, di-ammonium phosphate and ammoniumpolyphosphate, ammonium sulphate, and the less commonly used calciumnitrate, sodium nitrate, potassium nitrate and ammonium chloride. It isunderstood that a fertilizer composition can comprise one or acombination of the fertilizers described herein.

A typical urease inhibitor, alkyl thiophosphoric triamide, and, moreparticularly, NBPT (N-(n-butyl)-thiophosphoric triamide), however, facesdrawbacks in its use as NBPT is extremely difficult to handle. NBPT is asticky, waxy, heat and water sensitive material, which cannot be used inits solid form, as it is used at low concentrations making it difficultto evenly distribute on urea prills (i.e., large granules) and in soil.In order to evenly distribute the NBPT onto the urea, the NBPT should bedispersed into a carrier prior to being sprayed onto the urea. Thus, theuse of a solvent system containing the NBPT is desirable as, in itsliquid form, the solvent system is capable of distributing the NBPT intogranular urea (e.g., urea prills) and into liquid fertilizers containingurea. By introducing the NBPT to liquid fertilizers containing urea (forexample, urea-ammonium nitrate solutions or UAN) in a solvent system,the NBPT is capable of being better dispersed in the liquid fertilizer.

Dicyandiamide is useful as a nitrification inhibitor in aqueousagricultural applications, e.g., end use fertilizer compositions, butsimilar to urease inhibitors face similar drawbacks. Nitrificationinhibitors, such as dicyandiamide, generally have very low solubility(about 41 grams per liter (“g/l”) in water and so it is difficult toincorporate into the aqueous end use fertilizer compositions,particularly under field conditions. As nitrification inhibitors, suchas dicyandiamide, have a generally low solubility, they are used at lowconcentrations in water making it difficult to evenly distribute onurea-containing prills (i.e., large granules) and in soil. In order toevenly distribute the dicyandiamide onto the urea-containing prills orgranules, dicyandiamide should be dispersed into a solvent carrier priorto being sprayed onto the urea. Thus, the use of a solvent systemcontaining dicyandiamide (herein, also termed “DCD”) is desirable as, inits liquid form, the solvent system is capable of distributing thedicyandiamide onto urea granules or prills, urea ammonium nitrategranules or prills or, otherwise, urea-containing granules or prills,and into liquid fertilizers containing urea or urea ammonium nitrate. Byintroducing the dicyandiamide to liquid fertilizers containing urea (forexample, urea-ammonium nitrate solutions or UAN) in a solvent system,the dicyandiamide is capable of being better dispersed in the liquidfertilizer.

In one embodiment, concentrated fertilizer compositions includeconcentrated ammonium nitrate compositions, such as, for example, UAN18, UAN 28, UAN 30 and UAN 32.

Thus, it is desirable to have a solvent system containing alkylthiophosphoric triamide, and in particular, (N-(n-butyl)-thiophosphorictriamide), that has a favorable toxicological and/or ecological profileand desirable characteristics in terms of low volatility,biodegradability or ready biodegradability (i.e., readilybiodegradable), low toxicity or low hazard level. It is desirable tohave a solvent system containing dicyandiamide, that has a favorabletoxicological and/or ecological profile and desirable characteristics interms of low volatility, biodegradability or ready biodegradability(i.e., readily biodegradable), low toxicity or low hazard level. It isalso desirable to have a solvent system containing a combination ofdicyandiamide and an alkyl thiophosphoric triamide, in particular,(N-(n-butyl)-thiophosphoric triamide), that has a favorabletoxicological and/or ecological profile and desirable characteristics interms of low volatility, biodegradability or ready biodegradability(i.e., readily biodegradable), low toxicity or low hazard level.

The present invention described herein will become apparent from thefollowing detailed description and examples, which comprises in oneaspect, a liquid composition for use in agricultural applicationscomprising: at least one of a nitrification inhibitor or a ureaseinhibitor (and, in some embodiments, both a nitrification inhibitor anda urease inhibitor); and at least one organophosphate compound (or,hereinafter, synonymously referred to as an “organophosphate solvent”)of formula (VIII):

wherein R₁, R₂ and R₃, are each independently chosen from H, a C₁-C₁₆alkyl group, a C₁-C₁₆ alkenyl, group, a C₁-C₁₆ alkoxyalkyl group, aC₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkyl group, or an aryl group;provided that at least one of R₁, R₂ or R3 is not H. Optionally, theliquid composition can further comprise at least one co-solvent selectedfrom polar aprotic solvents, amine solvents, heterocyclic alcoholsolvents, and mixtures thereof. The liquid composition can furthercomprise one or more stabilizers.

In another aspect, described herein are methods of making a solid orconcentrated liquid fertilizer compositions comprising treating (e.g.,contacting or spray applying) one or more nitrogenous fertilizercompounds with a liquid inhibitor composition. The liquid inhibitorcomposition comprises at least one of a nitrification inhibitor or aurease inhibitor (or, in some embodiment, a combination of at least onenitrification inhibitor and at least one urease inhibitor), homogenouslydissolved or dispersed in a solvent comprising at least oneorganophosphate solvent according to formula (VIII), wherein R₁, R₂ andR₃ are as described above. The liquid inhibitor composition, in oneembodiment, further comprises at least one co-solvent selected frompolar aprotic solvents, amine solvents, heterocyclic alcohol solvents,and mixtures thereof.

The term treating, in one embodiment, includes spray applying the liquidinhibitor composition with the one or more nitrogenous fertilizercompounds. The term treating, in one embodiment, includes but is notlimited to contacting the inhibitor composition with the one or morenitrogenous fertilizer compounds. In one embodiment, the nitrificationinhibitor is dicyandiamide. In another embodiment, the urease inhibitoris an alkyl thiophosphoric triamide.

In yet another aspect, described herein are concentrated liquidfertilizer compositions comprising, based on weight of the composition:(a) up to about 99 wt %, by weight of composition, of one or morenitrogenous fertilizer compounds, (b) at least one of a dicyandiamide oran alkyl thiophosphoric triamide (or a combination of both), (c) asolvent comprising at least one organophosphate solvent according toformula (VIII), wherein R₁, R₂ and R₃ are as described above.

In a further aspect, described herein are concentrated liquid fertilizercompositions comprising, based on weight of the composition: (a) up toabout 99 wt %, by weight of composition, of one or more nitrogenousfertilizer compounds, (b) at least one of a dicyandiamide or an alkylthiophosphoric triamide (or, in some embodiments, both), (c) a solventcomprising at least one organophosphate solvent according to formula(VIII), (d) optionally, at least one co-solvent selected from polaraprotic solvents, amine solvents, heterocyclic alcohol solvents, andmixtures thereof, and (e) optionally, water. The concentrated liquidfertilizer compositions can further comprise one or more stabilizers.

In yet another aspect, described herein are solid or substantially solidfertilizer compositions comprising: (a) solid particles of one or morenitrogenous fertilizer compounds, and (b) an inhibitor compositioncomprising at least one of a dicyandiamide or an alkyl thiophosphorictriamide supported on at least a portion of the solid particles.

In another aspect, described herein are methods of making a liquid oraqueous fertilizer composition comprising contacting one or morenitrogenous fertilizer compounds, with a liquid inhibitor compositionthat comprises at least one of a nitrification inhibitor or a ureaseinhibitor, homogenously dissolved or dispersed in a solvent comprisingat least one organophosphate solvent according to formula (VIII),wherein R₁, R₂ and R₃ are as described above.

The solvent can, optionally, further comprise an co-solvent selectedfrom polar aprotic solvents, amine solvents, heterocyclic alcoholsolvents, and mixtures thereof.

In another aspect, the organic solvent is an organophosphate compoundhaving the formula (VIII)

wherein wherein R₁, R₂ and R₃, are each independently chosen from H, aC₁-C₁₆ alkyl group, a C₁-C₁₆ alkenyl, group, a C₁-C₁₆ alkoxyalkyl group,a C₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkyl group, or an arylgroup; provided that at least one of R₁, R₂ or R₃ is not H. In anotherembodiment, R₁, R₂ and R₃, are each independently chosen from H, aC₁-C₁₂ alkyl group, a C₁-C₁₂ alkenyl, group, a C₁-C₁₂ alkoxyalkyl group,a C₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkyl group, or an arylgroup; provided that at least one of R₁, R₂ or R₃ is not H. In oneembodiment, R₁, R₂ and R₃, are each independently chosen from H, a C₁-C₄alkyl group, a C₄-C₈ alkyl group, a C₁-C₁₂ alkenyl, group, a C₁-C₄alkoxyalkyl group, a C₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkylgroup, or an aryl group; provided that at least one of R₁, R₂ or R₃ isnot H.

In yet another embodiment, R₁, R₂ and R₃, are each independently chosenfrom a C₁-C₁₂ alkyl group, a C₁-C₁₂ alkenyl, group, a C₁-C₁₂ alkoxyalkylgroup, a C₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkyl group, or anaryl group. In one embodiment, R₁, R₂ and R₃, are each independentlychosen from a C₁-C₁₂ alkyl group, more typically, a C₂-C₈ alkyl group.

In another aspect, described herein are methods for fertilizing targetplants, comprising applying an aqueous end use fertilizer compositionthat comprises: (a) one or more nitrogenous fertilizer compounds, (b) atleast one of a dicyandiamide or an alkyl thiophosphoric triamide, (c) anorganic solvent having formula (VIII), wherein R₁, R₂ and R₃ are asdescribed above, and, (d) optionally, a co-solvent selected fromdimethyl sulfoxide, dimethyl formamide, the dimethyl ester of succinicacid, dimethyl ester of ethyl succinic acid, the dimethyl ester ofglutaric acid, the dimethyl ester of methyl glutaric acid, and thedimethyl ester of adipic acid, diethylene triamine, or monoethanolamine,methyl-5-(dimethylamino)-2-methyl-oxopentanoate, dimethylaminoethanol,triethanol amine, a heterocyclic alcohol according to structure (IIIb):

or mixtures thereof, and, optionally, (d) water, to the target plants orto an environment for the target plants. It is understood that the termheterocyclic alcohol includes dioxolane compounds. The end usefertilizer composition can also comprise, in some embodiments, at leastone stabilizer. In one embodiment, the stabilizer is monoethanolamine.

In one embodiment, the alkyl thiophosphoric triamide isN-(n-butyl)-thiophosphoric triamide. In another embodiment, the liquidcomposition further comprises a co-solvent selected from the groupconsisting of: (a) at least one dioxolane compound of formula (III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10; b) at least one dibasic ester; c) at least one compound of formula(IIa):R₃OOC-A-CONR₄R₅  (IIa),

wherein R₃ comprises a C₁-C₃₆ alkyl group; wherein R₄ and R₅individually comprise a C₁-C₃₆ alkyl group, wherein R₄ and R₅ canoptionally together form a ring; and wherein A is a linear or a brancheddivalent C₂-C₆ alkyl group; d) at least one alkyldimethylamide; e) atleast one alkyl lactate; f) ethyl levulinate; g) at least onealkyoxyalcohol, ether alcohol, amine alcohol, amino alcohol or alcohol;h) at least one glycerine or glycerine derivative; i) at least onealkylene carbonate; j) dimethylsulfoxide; and k) any combinationthereof. In one embodiment, the co-solvent is dimethylsulfoxide.

In another aspect, the present invention is directed to a nitrificationinhibitor composition comprising dicyandiamide dissolved in a liquidmedium that comprises an organic solvent selected from polar aproticsolvents, dibasic esters, amines, amino alcohols, heterocyclic alcohols,and mixtures thereof.

In yet another aspect, the present invention is directed to a method ofmaking a solid or concentrated liquid fertilizer composition comprisingtreating (e.g., contacting, spray applying, brushing, etc.) one or morenitrogenous fertilizer compounds with a nitrification inhibitorcomposition that comprises dicyandiamide dissolved in a liquid mediumthat comprises an organic solvent selected from polar aprotic solvents,amine solvents, heterocyclic alcohol solvents, and mixtures thereof.

In a further aspect, the present invention is directed to a concentratedliquid fertilizer composition comprising, by weight of the composition:

-   (a) up to about 99 wt % of one or more nitrogenous fertilizer    compounds,-   (b) dicyandiamide or an alkyl thiophosphoric triamide (or both    dicyandiamide and an alkyl thiophosphoric triamide);-   (c) at least one organophosphate solvent according to formula    (VIII), wherein R₁, R₂ and R₃ are as described above;-   (d) optionally, at least one co-solvent selected from polar aprotic    solvents, amine solvents, heterocyclic alcohol solvents, or mixtures    thereof, and-   (d) optionally, water.

In another aspect, the present invention is directed to a concentratedsolid fertilizer composition comprising:

-   (a) solid particles of one or more nitrogenous fertilizer compounds,    and-   (b) dicyandiamide or an alkyl thiophosphoric triamide supported on    at least a portion of the solid particles.

In yet another aspect, the present invention is directed to a method ofmaking an aqueous end use fertilizer composition comprising contactingone or more nitrogenous fertilizer compounds with a urease inhibitorcomposition that comprises an alkyl thiophosphoric triamide dissolved ina liquid medium that comprises an organic solvent selected from polaraprotic solvents, amine solvents, heterocyclic alcohol solvents, ormixtures thereof.

In a further aspect, the present invention is directed to a method forfertilizing target plants, comprising applying an aqueous end usefertilizer composition that comprises:

-   (a) one or more nitrogenous fertilizer compounds;-   (b) dicyandiamide, an alkyl thiophosphoric triamide, or a mixture    thereof;-   (c) at least one organophosphate solvent according to formula    (VIII), wherein R₁, R₂ and R₃ are as described above,-   (d) optionally, at least one organic solvent selected from dimethyl    sulfoxide, dimethyl formamide, the dimethyl ester of succinic acid,    dimethyl ester of ethyl succinic acid, the dimethyl ester of    glutaric acid, the dimethyl ester of methyl glutaric acid, and the    dimethyl ester of adipic acid, diethylene triamine, or    monoethanolamine, methyl-5-(dimethylamino)-2-methyl-oxopentanoate,    dimethylaminoethanol, triethanol amine, a heterocyclic alcohol    according to structure (IIIb):

Or mixtures thereof; and

-   (e) optionally, water,

to the target plants or to an environment for the target plants.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a chart illustrating the Residual Pressure of a ComparativeSample (without the organophosphate compound) labeled as “Unstabilized”and of Formulation 1 (with the organophosphate compound) labeled as“Stabilized”, both as a function of Temperature.

DETAILED DESCRIPTION

As used herein, the term “alkyl” means a saturated straight chain,branched chain, or cyclic hydrocarbon radical, including but not limitedto, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, t-butyl,pentyl, n-hexyl, and cyclohexyl.

As used herein, the term “aryl” means a monovalent unsaturatedhydrocarbon radical containing one or more six-membered carbon rings inwhich the unsaturation may be represented by three conjugated doublebonds, which may be substituted one or more of carbons of the ring withhydroxy, alkyl, alkenyl, halo, haloalkyl, or amino, including but notlimited to, phenoxy, phenyl, methylphenyl, dimethylphenyl,trimethylphenyl, chlorophenyl, trichloromethylphenyl, aminophenyl, andtristyrylphenyl.

As used herein, the term “alkylene” means a divalent saturated straightor branched chain hydrocarbon radical, such as for example, methylene,dimethylene, trimethylene.

As used herein, the term “alkoxyl” means an oxy radical that issubstituted with an alkyl group, such as for example, methoxyl, ethoxyl,propoxyl, isopropoxyl, or butoxyl, which may optionally be furthersubstituted on one or more of the carbon atoms of the radical.

As used herein, the term “alkoxyalkyl” means an alkyl radical that issubstituted with one or more alkoxy substituents, more typically a(C₁-C₂₂)alkyloxy-(C₁-C₆)alkyl radical, such as methoxymethyl, andethoxybutyl.

As used herein, the term “alkenyl” means an unsaturated straight orbranched hydrocarbon radical, more typically an unsaturated straight,branched, (which, in one particular embodiment, is C₁-C₇₅) hydrocarbonradical, that contains one or more carbon-carbon double bonds, such as,for example, ethenyl, n-propenyl, iso-propenyl.

As used herein, the term “arylalkyl” means an alkyl group substitutedwith one or more aryl groups, more typically a (C₁-C₁₈)alkyl substitutedwith one or more (C₆-C₁₄)aryl substituents, such as, for example,phenylmethyl, phenylethyl, and triphenylmethyl.

As used herein, the term “aryloxy” means an oxy radical substituted withan aryl group, such as for example, phenyloxy, methylphenyl oxy,isopropylmethylphenyloxy.

As used herein, the terminology “(C_(r)-C_(s))” in reference to anorganic group, wherein r and s are each integers, indicates that thegroup may contain from r carbon atoms to s carbon atoms per group.

In one embodiment, non-limiting examples of nitrification inhibitorscomprise any one or more of N-2,5-dichlorophenyl succinamic acid,dicyandiamide (DCD), zinc ethylene-bis-dithiocarbamate,2,4,6-triehloroaniline, pentachlorophenol, thio-urea, ammoniumthiosulphate (ATS) or 3,4-dimethypyrazole phosphate (DMPP).

In one embodiment, non-limiting examples of urease inhibitors compriseany one or more of N-butyl thiophosphoric triamide (NBPT),N-(w-butyl)phosphoric triamide, miophosphoryl triamide, cyclohexylphosphoric triamide, cyclohexyl thiophosphoric triamide, phosphorictriamide, hydroquinone, p-benzoquinone, hexamidocyclotriphosphazene,thiopyridines, thiopyrimidines, thiopyridine-N-oxides,N,A′-dihalo-2-imidazolidinone, N-halo-2-oxazolidinone, ammoniumthiosulphate (ATS), N-cyclohexyl phosphoric triamide (CHPT), phenylphosphorodiamidate (PPT) and 2-nitrophenyl phosphoric triamide (2-NPT).

Dicyandiamide is a known compound according to formula (I):

Dicyandiamide, also known as “2-cyanoguanidine”, is typically made bytreating cyanamide with base and is commercially available.

In one embodiment, the compositions according to the present inventioncomprise a urease inhibitor, such as an alkyl thiophosphoric triamide orammonium thiosulfate, a nitrification inhibitor, or a combination ofboth a urease inhibitor and a nitrification inhibitor.

In one embodiment, alkyl thiophosphoric triamide isN-(n-butyl)-thiophosphoric triamide (“NBPT”). The at least one of alkylthiophosphoric triamide or dicyandiamide (or combination thereof) can bepresent in the liquid agricultural composition at a lower range of 2% byweight of the composition. In another embodiment, the at least one ofalkyl thiophosphoric triamide or dicyandiamide or combination thereofcan be present in the liquid agricultural composition at a lower rangeof 3% by weight of the composition. The at least one of alkylthiophosphoric triamide or dicyandiamide or combination thereof can bepresent in the liquid agricultural composition at a lower range of 5% byweight of the composition.

In another embodiment, at least one of alkyl thiophosphoric triamide ordicyandiamide (or a combination of both) can be present in the liquidagricultural composition at a lower range of 0.5%, or 1%, or 2%, or 3%,or 4%, or 5%, 6%, or 8%, or 10% or 12% or 14%, by weight of thecomposition. The at least one of alkyl thiophosphoric triamide ordicyandiamide or combination thereof can be present in the liquidagricultural composition at an upper range of 75%, or 65%, or 60% byweight of the composition. In another embodiment, the at least one ofalkyl thiophosphoric triamide or dicyandiamide or combination thereofcan be present in the liquid agricultural composition at an upper rangeof 60% by weight of the composition. In another embodiment, the at leastone of alkyl thiophosphoric triamide or dicyandiamide or combinationthereof can be present in the liquid agricultural composition at anupper range of 55% by weight of the composition. In another embodiment,at least one of alkyl thiophosphoric triamide and/or dicyandiamide canbe present in the liquid agricultural composition at an upper range of59%, or 57%, or 55% or 53% or 50%, by weight of the composition. Inanother embodiment, at least one of alkyl thiophosphoric triamide and/ordicyandiamide can be present in the liquid agricultural composition atan upper range of 48%, or 46%, or 45% or 42% or 40%, by weight of thecomposition.

In another embodiment, the at least one of alkyl thiophosphoric triamideor dicyandiamide or combination thereof can be present in the liquidagricultural composition at an upper range of 70% by weight of thecomposition. In another embodiment, the at least one of alkylthiophosphoric triamide or dicyandiamide or combination thereof can bepresent in the liquid agricultural composition at an upper range of 65%by weight of the composition. In another embodiment, the at least one ofalkyl thiophosphoric triamide or dicyandiamide or combination thereofcan be present in the liquid agricultural composition at an upper rangeof 60% by weight of the composition. In another embodiment, the at leastone of alkyl thiophosphoric triamide or dicyandiamide or combinationthereof can be present in the liquid agricultural composition at anupper range of 55% by weight of the composition. In another embodiment,the at least one of alkyl thiophosphoric triamide or dicyandiamide orcombination thereof can be present in the liquid agriculturalcomposition at an upper range of 40% by weight of the composition. Inanother embodiment, the at least one of alkyl thiophosphoric triamide ordicyandiamide or combination thereof can be present in the liquidagricultural composition at an upper range of 35% by weight of thecomposition. In another embodiment, the at least one of alkylthiophosphoric triamide or dicyandiamide or combination thereof can bepresent in the liquid agricultural composition at an upper range of 30%by weight of the composition. In another embodiment, the at least one ofalkyl thiophosphoric triamide or dicyandiamide or combination thereofcan be present in the liquid agricultural composition at an upper rangeof 25% by weight of the composition.

In another embodiment, the at least one of alkyl thiophosphoric triamideor dicyandiamide can be present in the liquid agricultural compositionin an amount between about 7% by weight of the composition to about 55%by weight of the composition. In another embodiment, the at least one ofalkyl thiophosphoric triamide or dicyandiamide can be present in thecomposition in an amount between about 8% by weight of the compositionto about 50% by weight of the composition. In another embodiment, the atleast one of alkyl thiophosphoric triamide or dicyandiamide can bepresent in the liquid agricultural composition in an amount betweenabout 7% by weight of the composition to about 45% by weight of thecomposition. In another embodiment, the at least one of alkylthiophosphoric triamide or dicyandiamide can be present in the liquidagricultural composition in an amount between about 7% by weight of thecomposition to about 40% by weight of the composition. In anotherembodiment, the at least one of alkyl thiophosphoric triamide ordicyandiamide can be present in the liquid agricultural composition inan amount between about 7% by weight of the composition to about 35% byweight of the composition.

The at least one of alkyl thiophosphoric triamide or dicyandiamide canbe present in the composition in an amount between about 0.5% by weightof the composition and about 60% by weight of the composition or, inanother embodiment, can be present in the composition in an amountbetween about 1% by weight of the composition and about 40% by weight ofthe composition, and, in another embodiment, can be present in thecomposition in an amount between about 0.5% by weight of the compositionand about 20% by weight of the composition. In one particularembodiment, the at least one of alkyl thiophosphoric triamide ordicyandiamide is present in the composition in an amount between about1% by weight of the composition and about 30% by weight of thecomposition. The at least one of alkyl thiophosphoric triamide ordicyandiamide means that alkyl thiophosphoric triamide can be solelypresent, dicyandiamide can be solely present, or a combination of bothalkyl thiophosphoric triamide and dicyandiamide are present.

Compounds suitable as the organic solvent component of the compositionand methods of the present invention are organophosphate solventsaccording to formula (VIII) (wherein R₁, R₂ and R₃ are as describedabove), polar aprotic solvents, amine solvents, heterocyclic alcoholsolvents, or mixtures thereof, that form liquid, or otherwise stable,compositions with the nitrification and/or urease inhibitor, attemperatures of from −16° C. to 54° C., in other embodiments, −10° C. to40° C., in other embodiments, −5° C. to 40° C., in other embodiments,−2° C. to 40° C., or in other embodiments, 0° C. to 40° C.

In another embodiment, compounds suitable as the organic solventcomponent of the composition and methods of the present invention areorganophosphate solvents according to formula (VIII) (wherein R₁, R₂ andR₃ are as described above), polar aprotic solvents, amine solvents,heterocyclic alcohol solvents, or mixtures thereof, that form liquid, orotherwise stable, compositions with the nitrification and/or ureaseinhibitor at temperatures at or greater than −16° C., in alternativeembodiments, greater than −14° C., in other embodiments, greater than−12° C., in other embodiments, greater than −10° C., in furtherembodiments, greater than −8° C., in other embodiments, greater than −5°C., in other embodiments, greater than −3° C., in other embodiments,greater than −2° C., in other embodiments, greater than 0° C., in otherembodiments, greater than 2° C., in other embodiments, greater than 4°C., in other embodiments, greater than 5° C.

In some embodiments, at the specified temperature ranges or at greaterthan a specified temperature (as described herein), the liquidagricultural composition or liquid fertilizer composition is stable,meaning the urease and/or nitrification inhibitor(s) do not react withthe solvent or solvent component under anticipated manufacturing,storage, and use conditions. In one embodiment, at the specifiedtemperature ranges or at greater than a specified temperature (asdescribed herein), the liquid agricultural composition or liquidfertilizer composition is stable, meaning the liquid agriculturalcomposition or liquid fertilizer composition is or substantially is inone phase, i.e., no visible crystals, no visible precipitation, and/orno visible multiple liquid phases. In one embodiment, at the specifiedtemperature ranges or at greater than a specified temperature (asdescribed herein), the described liquid fertilizer composition isstable, meaning the degradation of the inhibitor component (which in oneembodiment is NBPT) is slowed or delayed as compared with a fertilizercomposition without the stabilizer or stabilizing component as describedherein. In one embodiment, the stabilizer or stabilizing component is anorganophosphate solvent of formula (VIII):

wherein R1, R2 and R3, are each independently chosen from H, a C1-C16alkyl group, a C1-C16 alkenyl, group, a C1-C16 alkoxyalkyl group, aC7-C30 alkylarylalkyl group, a C7-C30 arylalkyl group, or an aryl group;provided that at least one of R1, R2 or R3 is not H. In one embodiment,R1, R2 and R3, are each independently a C1-C16 alkyl group. In oneembodiment, R1, R2 and R3, are each independently a C1-C8 alkyl group.In one embodiment, R1, R2 and R3, are each independently a C1-C4 alkylgroup. In one embodiment, R1, R2 and R3, are each independently a C1-C2alkyl group.

In some embodiments, at high temperature ranges or at greater than aspecified temperature (as described herein), the liquid agriculturalcomposition or liquid fertilizer composition is stable, meaning theurease and/or nitrification inhibitor(s) do not react with the solventor solvent component under anticipated manufacturing, storage, and useconditions. In one embodiment, the liquid agricultural compositions orliquid fertilizer compositions are stable at a temperature greater than25° C. In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 27° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 29° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 30° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 32° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 34° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 35° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 37° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 40° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 42° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 44° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 45° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 47° C.In one embodiment, the liquid agricultural compositions or liquidfertilizer compositions are stable at a temperature greater than 50° C.

In one embodiment, at the specified temperature ranges or at greaterthan a specified temperature (as described herein), the liquidagricultural composition or liquid fertilizer composition is stable,meaning the liquid agricultural composition or liquid fertilizercomposition is or substantially is in one phase, i.e., no visiblecrystals, no visible precipitation, and/or no visible multiple liquidphases. In another embodiment, the liquid agricultural composition orliquid fertilizer composition is stable, meaning the liquid agriculturalcomposition or liquid fertilizer composition is or substantially is inone phase and shows little or slight discoloration.

In one embodiment, the solvent comprises at least one of anorganophosphate solvent according to formula (VIII) (wherein R₁, R₂ andR₃ are as described above), a polar aprotic solvent, amine solvent,heterocyclic alcohol solvent, or mixtures thereof in which dicyandiamidehas a solubility at 25° C. of greater than or equal to 50 grams perliter (g/l), more typically greater than or equal to 200 g/l. In oneembodiment, the solvent comprises at least one of an organophosphatesolvent according to formula (VIII) (wherein R₁, R₂ and R₃ are asdescribed above), optionally, with one or more co-solvents, in which ininhibitor component has a solubility at 25° C. of greater than or equalto 240 grams per liter (g/l), or in other embodiments, greater than orequal to 220 g/l, or in other embodiments, greater than or equal to 280g/l, or in other embodiments, greater than or equal to 300 g/l, or inother embodiments, greater than or equal to 340 g/l, or in otherembodiments, greater than or equal to 360 g/l, or in other embodiments,greater than or equal to 380 g/l. Reference to “inhibitor component”includes at least one nitrification inhibitor, or in some embodiments,at least one urease inhibitor, or in alternative embodiments, acombination of at least one urease inhibitor and at least onenitrification inhibitor. In one particular embodiment, the inhibitorcomponent comprises a combination of NBPT and DCD.

Suitable polar aprotic organic solvents include, for example,dichloromethane, dimethyl acetamide, dimethyl formamide, dimethylsulfoxide, ethyl acetate, hexamethylphosphoramide, dimethyl sulfone,sulfolane, 1,3-dimethyl-2-imidazoidinone,1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidone, methyl acetate, ethyllactate, methylpyrrolidone, tetrahydrofuran, propylene carbonate, anddibasic ester solvents.

In one embodiment, the formulations as described herein further compriseone or more stabilizers. In one embodiment, the organophosphate compoundof formula (VIII) is a stabilizer.

In one embodiment, the organophosphate compound of formula (VIII), whenadded to the formulations/compositions as described herein, providesstability to the formulation over a period of at least 24 hours. In oneembodiment, the organophosphate compound of formula (VIII), when addedto the formulations/compositions as described herein, provides stabilityto the formulation over a period of at least 48 hours. In a furtherembodiment, the organophosphate compound of formula (VIII), when addedto the formulations/compositions as described herein, provides stabilityto the formulation over a period of at least 72 hours. In anotherembodiment, the organophosphate compound of formula (VIII), when addedto the formulations/compositions as described herein, provides stabilityto the formulation over a period of at least 4 days, or at least 5 days,or at least 6 days, or at least 7 days, or at least 8 days, or at least9 days, or at least 10 days, or at least 11 days, or at least 12 days.In a further embodiment, the organophosphate compound of formula (VIII),when added to the formulations/compositions as described herein,provides stability to the formulation over a period of at least 14 days.

Suitable dibasic ester solvents include, for example, dialkyl esters ofdicarboxylic acids, more typically, the di(C₁-C₁₂)alkyl esters ofsaturated linear or branched (C₂-C₈)aliphatic carboxylic acids or amixture thereof. In one embodiment, the dibasic ester componentcomprises one or more compounds according to structure (II):R¹OOC-A-CONR²R³  (II)wherein:

A is a divalent linear or branched (C₂-C₈)aliphatic group, and

R¹, R², and R³ are each independently (C₁-C₁₂)alkyl, (C₁-C₁₂)aryl,(C₁-C₁₂)alkaryl or (C₁-C₁₂)arylalkyl, and R² and R³ may each optionallybe substituted with one or more hydroxyl groups.

In one embodiment, the dibasic ester solvent component of thecompositions and methods of the present invention comprises one or moredimethyl esters of saturated linear or branched (C₄-C₆)aliphaticcarboxylic acids, such the dimethyl ester of succinic acid, dimethylester of ethyl succinic acid, the dimethyl ester of glutaric acid, thedimethyl ester of methyl glutaric acid, and the dimethyl ester of adipicacid, and mixtures thereof. In one embodiment, the dibasic estercomponent comprises the dimethyl ester of succinic acid, the dimethylester of glutaric acid, and optionally, the dimethyl ester of adipicacid, In another embodiment, the dibasic ester component comprises thedimethyl ester of ethyl succinic acid, the dimethyl ester of methylglutaric acid, and optionally, the dimethyl ester of adipic acid.

In one embodiment, the dibasic ester solvent component of thecompositions and methods of the present invention comprises one or moredialkyl esters of saturated linear or branched (C₄-C₆)aliphaticcarboxylic acids, such the dialkyl ester of succinic acid, dialkyl esterof ethylsuccinic acid, the dialkyl ester of glutaric acid, the dialkylester of methylglutaric acid, and the dialkyl ester of adipic acid, andmixtures thereof. In one embodiment, the dibasic ester componentcomprises the dialkyl ester of succinic acid, the dialkyl ester ofglutaric acid, and optionally, the dimethyl ester of adipic acid, Inanother embodiment, the dibasic ester component comprises the dialkyldimethyl ester of ethylsuccinic acid, the dialkyl ester ofmethylglutaric acid, and optionally, the dialkyl ester of adipic acid.Each alkyl group in the dialkyl group, one embodiment, individuallycomprise a C₁-C₈ alkyl. In another embodiment, each alkyl group in thedialkyl group, one embodiment, individually comprise a C₁-C₄ alkyl. Inanother embodiment, each alkyl group in the dialkyl group, oneembodiment, individually comprise a C₁-C₆ alkyl.

Suitable amine solvents include primary amines, includingmonoalkylamines, such as propylamine, secondary amines, includingdialkyl amines and diaryl amines, such as dimethylamine anddiphenylamine, and tertiary amines, such as diethylene triamine andmethyl-5-(dimethylamino)-2-methyl-oxopentanoate.

In one embodiment, the amine solvent component of the compositions andmethods of the present invention is selected from aliphatic or aromaticprimary, secondary, or tertiary amines that do not comprise anyfunctional group other than one or more amino groups.

In one embodiment, the amine solvent component of the compositions andmethods of the present invention is selected from aliphatic or aromaticprimary, secondary, or tertiary amines may optionally further compriseone or more additional functional groups, such as hydroxyalkyl groups,hydroxyl groups, carbonyl groups, or alkyl ester groups, other than oneor more amino groups.

In one embodiment, the organic solvent component of the compositions andmethods of the present invention comprises an amino alcohol. Compoundssuitable as the amino alcohol solvent component of the compositions andmethods of the present invention are those compounds that comprise atleast one primary, secondary, or tertiary amino moiety per molecule andat least one hydroxyalkyl moiety per molecule, more typically In oneembodiment, the amino alcohol is a linear, branched, or cyclic,saturated or unsaturated hydrocarbon that is substituted on at least onecarbon atom with an amino group and on at least one other carbon atomwith hydroxyalkyl or hydroxyl group, such as monoethanolamine,ethylaminoethanol, dimethylaminoethanol, isopropylaminoethanol,diethanolamine, triethanolamine, methylaminoethanol, aminopropanol,methylaminopropanol, dimethylaminopropanol, aminobutanol,dimethylaminobutanol, aminobutanediol, trihydroxymethylaminoethane,diethylaminopropanediol, 1-amino-cyclopentane methanol, and aminobenzylalcohol, or a heterocyclic ring that comprises at least one nitrogenatom as a ring member and/or is substituted on at least one carbon atomwith an amino group and that is substituted on at least one other carbonatom with a hydroxyalkyl or hydroxyl group, such asmethylaminomethyl-1,3-dioxolane.

Suitable heterocyclic alcohol solvents include, for example, 5- or6-membered heterocyclic rings that include 1 or 2 oxygen atoms as ringmember, that are substituted on at least one carbon atom of the ringwith a (C₁-C₆)hydroxyalkyl group, and that may optionally be substitutedon one or more carbon atoms of the ring with one or more (C₁-C₄)alkylgroups. It is understood that the term heterocyclic alcohol includesdioxolane compounds. In one embodiment, the heterocyclic alcoholcomponent of the present invention comprises a one or more compoundsselected from heterocyclic alcohols according to structures (IV), (IVa),(V), (VI), and (VII):

wherein n=1 or 2,

In one embodiment, the organic solvent component of the composition andmethods of the present invention comprises one or more organophosphatesolvents as described herein, polar aprotic solvents, one or moredibasic ester compounds according to structure (II), one or more aminoalcohols, one or more tertiary amines, one or more heterocyclic alcoholsaccording to structure (III), or mixtures thereof.

In one embodiment, the organic solvent component of the composition andmethods of the present invention comprises dimethyl sulfoxide, dimethylformamide, the dimethyl ester of succinic acid, dimethyl ester of ethylsuccinic acid, the dimethyl ester of glutaric acid, the dimethyl esterof methyl glutaric acid, and the dimethyl ester of adipic acid,diethylene triamine, or monoethanolamine,methyl-5-(dimethylamino)-2-methyl-oxopentanoate, dimethylaminoethanol,triethanol amine, a heterocyclic alcohol according to structure (III),or a mixture thereof.

In one embodiment, the organic solvent component of the liquidagricultural composition comprises at least one organophosphate compoundhaving the formula (VIII)

wherein wherein R₁, R₂ and R₃, are each independently chosen from H, aC₁-C₁₆ alkyl group, a C₁-C₁₆ alkenyl, group, a C₁-C₁₆ alkoxyalkyl group,a C₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkyl group, or an arylgroup; provided that at least one of R₁, R₂ or R₃ is not H. In anotherembodiment, R₁, R₂ and R₃, are each independently chosen from H, aC₁-C₁₂ alkyl group, a C₁-C₁₂ alkenyl, group, a C₁-C₁₂ alkoxyalkyl group,a C₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkyl group, or an arylgroup; provided that at least one of R₁, R₂ or R₃ is not H. In oneembodiment, R₁, R₂ and R₃, are each independently chosen from H, a C₁-C₄alkyl group, a C₄-C₈ alkyl group, a C₁-C₁₂ alkenyl, group, a C₁-C₄alkoxyalkyl group, a C₇-C₃₀ alkylarylalkyl group, a C₇-C₃₀ arylalkylgroup, or an aryl group; provided that at least one of R₁, R₂ or R₃ isnot H. In one embodiment, the organophosphate compound of formula (VIII)is the stabilizer.

In yet another embodiment, R₁, R₂ and R₃, are each independently chosenfrom a linear or branched C₁-C₁₂ alkyl group, a linear or branchedC₁-C₁₂ alkenyl, group, a linear or branched C₁-C₁₂ alkoxyalkyl group, alinear or branched C₇-C₃₀ alkylarylalkyl group, a linear or branchedC₇-C₃₀ arylalkyl group, or an aryl group. In one embodiment, R₁, R₂ andR₃, are each independently chosen from a C₁-C₁₂ alkyl group, moretypically, a C₂-C₈ alkyl group.

In one embodiment, R₁, R₂ and R₃, are each independently a C₁-C₃ alkylgroup, typically an ethyl group. In another embodiment, R₁, R₂ and R₃,are each independently a branched C₁-C₁₂ alkyl group, typically, a2-ethylhexyl group. In one embodiment, R₁, R₂ and R₃, are eachindependently a C₁-C₁₂ alkoxyalkyl group, typically a butoxyethyl group.

In one embodiment, the organic solvent component of the composition andmethods of the present invention comprises dimethyl sulfoxide, dimethylformamide, diethylene triamine, monoethanolamine, or a mixture thereof.

In one embodiment, the organic solvent component of the composition andmethods of the present invention comprises a mixture of at least oneorganophosphate solvent according to formula (VIII), wherein R₁, R₂ andR₃ are as described above, and dimethyl sulfoxide.

In one embodiment, a compound utilized as the solvent or as a componentin the solvent blend is a compound of general formula (II):R₃OOC-A-CONR₄R₅  (II),

According to one embodiment, the expression “compound” denotes anycompound corresponding to the general formula (II). In otherembodiments, the term “compound” also refers to mixtures of severalmolecules corresponding to general formula (II). It may therefore be amolecule of formula (II) or a mixture of several molecules of formula(II), wherein both fall under the definition of the term “compound” whenreferring to formula (II).

The R₃, R₄ and R₅ groups can be, in some embodiments, identical or, inother embodiment, different. In one embodiment, may be groups chosenfrom C₁-C₂₀ alkyl, aryl, alkaryl or arylalkyl groups or the phenylgroup. In another embodiment, may be groups chosen from C₁-C₁₂ alkyl,aryl, alkaryl or arylalkyl groups or the phenyl group. Mention is madeespecially of Rhodiasolv® PolarClean (Manufactured by Rhodia Inc. ofCranbury, N.J.). The R₄ and R₅ groups may optionally be substituted. Inone particular embodiment, the groups are substituted with hydroxylgroups.

In one embodiment, R₃ group is chosen from methyl, ethyl, propyl,isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, isoamyl, n-hexyl,cyclohexyl, 2-ethylbutyl, n-octyl, isooctyl, 2-ethylhexyl, tridecylgroups.

R₄ and R₅ groups, which are identical or different, in one embodiment,may especially be chosen from methyl, ethyl, propyl (n-propyl),isopropyl, n-butyl, isobutyl, n-pentyl, amyl, isoamyl, hexyl, cyclohexylor hydroxyethyl groups. The R₄ and R₅ groups may also be such that theyform, together with the nitrogen atom, a morpholine, piperazine orpiperidine group. According to some embodiments, R₄ and R₅ are eachmethyl, or R₄ and R₅ are each ethyl, or R₄ and R₅ are each hydroxyethyl.

According to one embodiment, if A comprises a linear group of formula—CH₂—CH₂— and/or of formula —CH₂—CH₂—CH₂—CH₂— and/or of formula —(CH₂)₈—then it is a mixture of A groups. According to one particularembodiment, if A is linear, then it is a mixture of A groups, forexample a mixture of two or three —CH₂—CH₂-(ethylene);—CH₂—CH₂—CH₂-(n-propylene); and —CH₂—CH₂—CH₂—CH₂-(n-butylene) groups (orisomers thereof).

According to a first particular embodiment of the invention, the A groupis a divalent linear alkyl group chosen from the groups of the followingformulae: —CH₂—CH₂-(ethylene); —CH₂—CH₂—CH₂-(n-propylene);—CH₂—CH₂—CH₂—CH₂-(n-butylene), and mixtures thereof.

In one embodiment, the inhibitor composition of the present inventioncomprises, based on 100 parts by weight (“pbw”) of the composition:

from about 4 to about 60 pbw, more typically from about 10 to about 55pbw, and even more typically from about 20 to about 40 pbwdicyandiamide, and

from about 55 to about 96 pbw, more typically from about 58 to about 90pbw, and even more typically from about 60 to about 80 pbw of theorganic solvent.

In one embodiment, the inhibitor composition of the present inventioncomprises one or more urease inhibitors, such as, for example, NBPT orammonium thiosulfate.

The nitrogenous fertilizer compound is treated with the inhibitorcomposition by contacting the nitrogenous fertilizer composition withthe inhibitor composition described herein (e.g., nitrificationinhibitor or urease inhibitor or a combination of both). The nitrogenousfertilizer composition may be in solid or liquid form.

Suitable nitrogenous fertilizers are those containing a nitrogenouscompound such as urea, nitrate salts, ammonium salt, or a mixturethereof, such as ammonium nitrate, ammonium sulfate, ammoniumthiosulfate, ammonium polysulfide, ammonium phosphates, ammoniumchloride, ammonium bicarbonate, anhydrous ammonia, calcium nitrate,nitrate soda, calcium cyanamide. In one embodiment, the nitrogenousfertilizer comprises ammonium nitrate. Suitable ammoniumnitrate-containing fertilizers include, for example, UAN 18, UAN 28, andUAN 30.

In one embodiment, the nitrogenous fertilizer composition is in solidparticulate form, and the contacting of the nitrogenous fertilizercomposition with the inhibitor composition is conducted by, for example,spraying the composition of the present invention on the particles ofsolid fertilizer composition.

In one embodiment, the concentrated fertilizer composition of thepresent invention is a solid nitrification-inhibited fertilizercomposition that comprises, based on 100 pbw of the composition:

from about 60 pbw to about 99.999, more typically from about 70 pbw toabout 99.999, and even more typically from about 80 pbw to about 99.999solid particles of one or more nitrogenous fertilizer compounds, and

from about 0.001 to about 40 pbw, more typically from about 0.001 toabout 30 pbw, and even more typically from about 0.001 to about 20 pbw,dicyandiamide.

In one embodiment, the solid nitrification-inhibited fertilizercomposition of the present invention further comprises one or moreurease inhibitors, more typically NBPT.

In one embodiment, the end use fertilizer composition of the presentinvention is made by combining the inhibitor composition of the presentinvention with a solid nitrogenous fertilizer to form a solidnitrification-inhibited fertilizer composition and subsequentlydissolving the solid nitrification-inhibited fertilizer composition inan aqueous medium, typically water, in a ratio of up to about 500 pbw,more typically from 100 to 500 pbw and even more typically from about100 to about 300 pbw, of the aqueous medium per 1 pbw of the solidnitrification-inhibited fertilizer composition.

In one embodiment, the fertilizer compound is in liquid form and thecontacting of the fertilizer composition with the inhibitor compositionis conducted by mixing the inhibitor composition with the liquidfertilizer composition.

In one embodiment, the concentrated fertilizer composition of thepresent invention is a concentrated liquid nitrification-inhibitedfertilizer composition that comprises, based on 100 pbw of thecomposition:

from about 20 to about 99.989 pbw, more typically from about 30 to about99.985 pbw, and even more typically from about 40 to about 99.98 pbw ofone or more nitrogenous fertilizer compounds,

from about 0.001 to 40 pbw, more typically from about 0.005 to 30 pbw,and even more typically from about 0.01 to 20 pbw dicyandiamide, and

from about 0.01 to 60 pbw, more typically from about 0.01 to about 40pbw, and even more typically from about 0.01 to about 30 pbw of theorganic solvent or solvent mixture, as described herein.

In one embodiment, the concentrated liquid nitrification-inhibitedfertilizer composition of the present invention further comprises one ormore urease inhibitors, more typically NBPT.

In one embodiment, the end use fertilizer composition of the presentinvention is made by combining the inhibitor composition of the presentinvention with a concentrated nitrogenous fertilizer to form aconcentrated liquid nitrification-inhibited fertilizer composition andsubsequently diluting the concentrated liquid nitrification-inhibitedfertilizer composition with an aqueous medium, typically water in aratio of up to about 500 pbw, more typically from about 10 to about 500pbw and even more typically from about 100 to about 300 pbw, of theaqueous medium per 1 pbw concentrated liquid nitrogenous fertilizercomposition.

In one embodiment, the end use fertilizer composition of the presentinvention is made by combining the inhibitor composition of the presentinvention, a solid or concentrated liquid nitrogenous fertilizer, and anaqueous medium.

In one embodiment, the end use fertilizer composition of the presentinvention is an aqueous liquid composition that comprises water, one ormore nitrogenous fertilizer compounds, and dicyandiamide, typically inan amount of from 2×10⁻⁶ pbw to about 4 pbw dicyandiamide per 100 pbw ofthe end use fertilizer composition.

In one embodiment, the end use fertilizer composition of the presentinvention comprises water and based on 100 parts by weight of thecomposition:

from about 0.04 to about 10 pbw, more typically from about 0.06 to about10 pbw, and even more typically from about 0.08 pbw to about 10 pbw toof one or more nitrogenous fertilizer compounds,

from about 2×10⁻⁶ to about 4 pbw, more typically from about 1×10⁻⁵ toabout 3 pbw, and even more typically from about 2×10⁻⁴ to about 2 pbwdicyandiamide, and

from about 2×10⁻⁴ to about 6 pbw, more typically from about 2×10⁻⁴ toabout 4 pbw, and even more typically from about 2×10⁻⁴ to about 3 pbw ofthe organic solvent.

In one embodiment, the end use fertilizer composition of the presentinvention comprises one or more urease inhibitors, more typically NBPT,alone or in combination with the nitrification inhibitor.

In one embodiment, the end use fertilizer composition of the presentinvention comprises from about 0.001 to about 5 pbw, more typically fromabout 0.01 to about 2 pbw dicyandiamide per 100 pbw of the one or morenitrogenous fertilizer compounds.

In one embodiment, the end use fertilizer composition is applied totarget plants or to an environment for the target plants, i.e., toground on or within which the target plants are growing or to be grown,at a rate of from about 0.01 pounds to about 5 pounds of the fertilizercomposition, more typically from about 0.05 pounds to about 2 pounds ofthe fertilizer composition, per 100 square feet of ground.

In one embodiment, the end use fertilizer composition is applied totarget plants or to an environment for the target plants at a rateeffective to provide a dosage of nitrogenous fertilizer compound of fromabout 0.01 pounds to about 5 pounds of fertilizer compound, moretypically from about 0.05 pounds to 2 pounds of fertilizer compound, per100 square feet of ground.

In one embodiment, the end use fertilizer composition is applied totarget plants or to an environment for the target plants at a rateeffective to provide a dosage of dicyandiamide of from about 0.01 poundsto 5 pounds of dicyandiamide, more typically from about 0.05 pounds to 2pounds of dicyandiamide, per 1000 square feet of ground.

The composition of the present invention provides improved ease ofhandling of dicyandiamide, improved solubility characteristics, lowtoxicity of the organic solvents; good storage characteristics, andexcellent miscibility with aqueous compositions, such as aqueousnitrogenous fertilizer formulations.

In one embodiment the composition comprises, by weight of composition,at least 50 wt % of DCD and/or NBPT, the remainder being solvent or amixture of solvents. By way of example, in one embodiment, thefertilizer composition comprises, by weight of composition, at least 50wt % of NBPT and less than or equal to 50 wt % of a solvent blend ofDMSO and at least one organophosphate solvent according to formula(VIII), wherein R₁, R₂ and R₃ are as described above. By way of anotherexample, in one embodiment, the fertilizer composition comprises, byweight of composition, at least 50 wt % of DCD and 50 wt % of a solventblend of DMSO and at least one organophosphate solvent according toformula (VIII), wherein R₁, R₂ and R₃ are as described above. By way ofanother example, in one embodiment, the fertilizer compositioncomprises, by weight of composition, at least 50 wt % of DCD and lessthan or equal to 50 wt % of at least one organophosphate solventaccording to formula (VIII), wherein R₁, R₂ and R₃ are as describedabove. Optionally, other components such as dyes and the like can beadded.

In one embodiment the composition comprises, by weight of composition,at least 25 wt % or 30 wt % of DCD and/or NBPT, the remainder beingsolvent or a mixture of solvents. By way of example, in one embodiment,the fertilizer composition comprises, by weight of composition, at least25 wt % of a combination of DCD and NBPT and less than or equal to 70 wt% of a solvent blend of: (i) at least one dioxolane compound of formula(III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10; and

(ii) at least one organophosphate solvent according to formula (VIII),wherein R₁, R₂ and R₃ are as described above. Optionally, othercomponents such as dyes and the like can be added.

By way of example, in another embodiment, the fertilizer compositioncomprises, by weight of composition, at least 25 wt %, typically asleast 30 wt %, of a combination of DCD and NBPT, and less than or equalto 70 wt % of a solvent blend of: (i) at least one dioxolane compound offormula (III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10; and

(ii) at least one organophosphate solvent according to formula (VIII),wherein R₁, R₂ and R₃ are as described above. Optionally, othercomponents such as dyes and the like can be added.

In one embodiment the composition comprises, by weight of composition,greater than 40 pbw of DCD and/or NBPT, the remainder being solvent or amixture of solvents.

In one embodiment the composition comprises, by weight of composition,greater than 35 pbw of DCD and/or NBPT, the remainder being solvent or amixture of solvents.

In one embodiment the composition comprises, by weight of composition,greater than 45 pbw of DCD and/or NBPT, the remainder being solvent or amixture of solvents. By way of example, in one embodiment, thefertilizer composition comprises, by weight of composition, 45 wt % ofDCD and 55 wt % of a solvent blend of: (i) at least one dioxolanecompound of formula (III), wherein R₆ and R₇ are as described above; and

(ii) at least one organophosphate solvent according to formula (VIII),wherein R₁, R₂ and R₃ are as described above.

In one embodiment the composition comprises, by weight of composition,greater than 55 pbw of DCD and/or NBPT, the remainder being solvent or amixture of solvents. By way of example, in one embodiment, thefertilizer composition comprises, by weight of composition, at least 55wt % of DCD and/or NBPT and less than or equal to 45 wt % of a solventblend of: (i) at least one dioxolane compound of formula (III), whereinR₆ and R₇ are as described above; and

(ii) at least one organophosphate solvent according to formula (VIII),wherein R₁, R₂ and R₃ are as described above.

Experiments:

Formulation 1 DV-10607 Components wt % (by weight of total formulation)NBPT 50.0 DMSO 39.7 TEP 9.9 Blue Dye 0.24 Yellow Dye 0.16 Total 100

Formulation 2 DV-10662 Components wt % (by weight of total formulation)DCD 24.0 NBPT 6.0 DMSO 68.2 TEP 1.5 Blue Dye 0.18 Yellow Dye 0.12 Total100

A Comparative Sample was prepared with the same NBPT and solvent sourceas Formulation 1, except the Comparative Sample did not contain TEP as astabilizer. Both Formulation 1 and the Comparative Sample were set asideat 45° C. for 2 weeks. It was observed that both Formulation 1 and theComparative Sample showed color evolution, as both started colorless.After 2 weeks it was observed that the Comparative Sample turned a darkamber color. However, Formulation 1 turned a slight yellow, transparentcolor, which indicated a lower NBPT degradation curve versus theComparative Example, which did not containing the stabilizer.

Referring to FIG. 1, both Formulation 1 and the Comparative Sample wereanalyzed by ARC (Accelerated Rate calorimetry) up to 100° C. in astainless steel test cell using standard HWS (Heat-wait-search mode)methodology. Test were performed under an air atmosphere. An onset of˜76° C. was determined for the unstabilized sample (i.e., theComparative Sample), while no onset was determined for the stabilizedone (i.e., Formulation 1). It is believed that this onset is an exothermreaction giving an indication of instability. Referring back to FIG. 1,a chart illustrates the residual pressure of a Comparative Sample(without the organophosphate compound, i.e., unstabilized) and ofFormulation 1 (with the organophosphate compound, i.e., stabilized),both as a function of Temperature.

Lower residual pressure is an indication of lower volatile components,an indirect measure of degradation. In other words, there were lessvolatile components measured for the Stabilized formulation(Formulation 1) over the temperature range as compared to theComparative Sample. The measurement of less volatile components over thetemperature range indicates that less NBPT is degraded in Formulation 1as compared to the Comparative Sample (i.e., more NBPT was degraded inthe Comparative Sample). This supports the visual observation of the twosamples after 2 weeks at 45° C., in which the Comparative Sample turneda much darker color, indicating more degradation of NBPT related toFormulation 1.

What is claimed is:
 1. A liquid agricultural composition comprising aurease inhibitor comprising N-butyl thiophosphoric triamide or a mixturecomprising the urease inhibitor and a nitrification inhibitor; anorganophosphate solvent of formula (VIII):

wherein R₁, R₂ and R₃, are each a C₂ alkyl group; dimethylsulfoxide; andoptionally, at least one organic co-solvent selected from: (a) at leastone dioxolane compound of formula (III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10; b) at least one dibasic ester; c) at least one compound of formula(IIa):R₃OOC-A-CONR₄R₅  (IIa), wherein R₃ comprises a C₁-C₃₆ alkyl group;wherein R₄ and R₅ individually comprise a C₁-C₃₆ alkyl group, wherein R₄and R₅ can optionally together form a ring; and wherein A is a linear ora branched divalent C₂-C₆ alkyl group; d) at least onealkyldimethylamide; e) at least one alkyl lactate; f) ethyl levulinate;g) at least one alkyoxyalcohol, ether alcohol, amine alcohol, aminoalcohol or alcohol; h) at least one glycerine or glycerine derivative;or i) at least one alkylene carbonate, wherein the urease inhibitor orthe mixture comprising the urease inhibitor and the nitrificationinhibitor is 0.5 to 60 wt %, by total weight of the composition.
 2. Theliquid agricultural composition of claim 1, wherein the nitrificationinhibitor is present and comprises dicyandiamide.
 3. The liquidagricultural composition of claim 1, wherein the at least one co-solventis present and comprises at least one dioxolane compound of formula(III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10.
 4. The liquid agricultural composition of claim 1, wherein theurease inhibitor is 14 to 60 wt by total weight of the composition, %,wherein the organophosphate solvent comprises triethyl phosphate,wherein for 100 parts by weight total N-butyl thiophosphoric triamide,organophosphate solvent, dimethylsulfoxide and organic co-solvent thereis 30 to 60 parts N-butyl thiophosphoric triamide.
 5. The liquidagricultural composition of claim 1, wherein the urease inhibitor or themixture comprising the urease inhibitor and the nitrification inhibitoris present up to 55 wt %, by total weight of the composition.
 6. Theliquid agricultural composition of claim 1, wherein the urease inhibitoror the mixture comprising the urease inhibitor and the nitrificationinhibitor is present at greater than 45 and up to 55 wt %, by totalweight of the composition, wherein the organophosphate solvent comprisestriethyl phosphate, wherein for 100 parts by weight total N-butylthiophosphoric triamide, organophosphate solvent, dimethylsulfoxide andorganic co-solvent there is 30 to 55 parts N-butyl thiophosphorictriamide.
 7. The composition of claim 1, wherein triethyl phosphate isthe organophosphate solvent, wherein the urease inhibitor is N-butylthiophosphoric triamide and is 30 to 60 wt %, by total weight of thecomposition, wherein for 100 parts by weight total N-butylthiophosphoric triamide, organophosphate solvent and dimethylsulfoxidethere is greater than 40 and up to 60 parts N-butyl thiophosphorictriamide.
 8. The composition of claim 7, wherein the urease inhibitor isN-butyl thiophosphoric triamide and is 40 to 55 w t%, by total weight ofthe composition, wherein for 100 parts by weight total N-butylthiophosphoric triamide, triethyl phosphate and dimethylsulfoxide thereis greater than 45 and up to 55 parts N-butyl thiophosphoric triamide.9. A method of making a solid or concentrated liquid fertilizercomposition comprising treating one or more nitrogenous fertilizercompounds with a liquid inhibitor composition that comprises a ureaseinhibitor, comprising N-butyl thiophosphoric triamide, dispersed in aliquid medium comprising at least one solvent of formula (VIII):

wherein R₁, R₂ and R₃, are each independently a C₂ alkyl group anddimethylsulfoxide and optionally a co-solvent, and optionally anitrification inhibitor, wherein the urease inhibitor or a mixturecomprising the urease inhibitor and the nitrification inhibitor is 0.5to 60 wt %, by total weight of the composition.
 10. The method of claim9, wherein the nitrification inhibitor is present, wherein thenitrification inhibitor comprises dicyandiamide.
 11. The method of claim9, wherein the liquid inhibitor composition further comprisesmonoethanolamine as a stabilizer.
 12. A concentrated liquid fertilizercomposition comprising, based on 100 parts by weight of the composition:(a) up to about 99 parts by weight of one or more nitrogenous fertilizercompounds, (b) a urease inhibitor comprising N-butyl thiophosphorictriamide, (c) organophosphate solvent of formula (VIII):

wherein R₁, R₂ and R₃, are each a C₂ alkyl group, and (d)dimethylsulfoxide and optionally at least one co-solvent, and (e)optionally a nitrification inhibitor, wherein the urease inhibitor or amixture comprising the urease inhibitor and the nitrification inhibitoris 0.5 to 60 wt %, by total weight of the urease inhibitor, theorganophosphate solvent, the dimethylsulfoxide, if present theco-solvent and, if present the nitrification inhibitor.
 13. Theconcentrated liquid fertilizer composition of claim 12, wherein thenitrification inhibitor is present and comprises dicyandiamide.
 14. Theconcentrated liquid fertilizer composition of claim 12, wherein the atleast one co-solvent is present and comprises at least one member of thegroup consisting of: (a) at least one dioxolane compound of formula(III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10; b) at least one dibasic ester; c) at least one compound of formula(IIa):R₃OOC-A-CONR₄R₅  (IIa), wherein R₃ comprises a C₁-C₃₆ alkyl group;wherein R₄ and R₅ individually comprise a C₁-C₃₆ alkyl group, wherein R₄and R₅ can optionally together form a ring; and wherein A is a linear ora branched divalent C₂-C₆ alkyl group; d) at least onealkyldimethylamide; e) at least one alkyl lactate; f) ethyl levulinate;g) at least one alkyoxyalcohol, ether alcohol, amine alcohol, aminoalcohol or alcohol; h) at least one glycerine or glycerine derivative;i) at least one alkylene carbonate; and k) any combination thereof. 15.A method of making an aqueous end use fertilizer composition comprisingcontacting one or more nitrogenous fertilizer compounds with a ureaseinhibitor composition, the urease inhibitor composition comprising aurease inhibitor dispersed in a liquid medium, the urease inhibitorcomprising N-butyl thiophosphoric triamide, the liquid medium comprisingsolvent of formula (VIII):

wherein R₁, R₂ and R₃, are each a C₂ alkyl group, and dimethylsulfoxide,and optionally a nitrification inhibitor, wherein the urease inhibitoror a mixture comprising the urease inhibitor and the nitrificationinhibitor is 0.5 to 60 wt %, by total weight of the urease inhibitorcomposition.
 16. The method of claim 15 wherein the liquid mediumfurther comprises at least one co-solvent selected from the groupconsisting of: (a) at least one dioxolane compound of formula (III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10; b) at least one dibasic ester; c) at least one compound of formula(IIa):R₃OOC-A-CONR₄R₅  (IIa), wherein R₃ comprises a C₁-C₃₆ alkyl group;wherein R₄ and R₅ individually comprise a C₁-C₃₆ alkyl group, wherein R₄and R₅ can optionally together form a ring; and wherein A is a linear ora branched divalent C₂-C₆ alkyl group; d) at least onealkyldimethylamide; e) at least one alkyl lactate; f) ethyl levulinate;g) at least one alkyoxyalcohol, ether alcohol, amine alcohol, aminoalcohol or alcohol; h) at least one glycerine or glycerine derivative;and i) at least one alkylene carbonate.
 17. The method of claim 15,wherein the nitrification inhibitor is present, wherein thenitrification inhibitor comprises dicyandiamide.
 18. A liquidagricultural composition consisting of at least one inhibitor selectedfrom the group consisting of a urease inhibitor and a mixture of theurease inhibitor and a nitrification inhibitor, wherein N-butylthiophosphoric triamide and optionally dicyandiamide is the at least oneinhibitor; an organophosphate solvent of formula (VIII):

wherein R₁, R₂ and R₃, are each a C₂ alkyl group; dimethylsulfoxide;optionally, at least one co-solvent selected from: (a) at least onedioxolane compound of formula (III):

wherein R₆ and R₇ individually comprises a hydrogen, an alkyl group, analkenyl group, or a phenyl group, wherein n is an integer of from 1 to10; b) at least one dibasic ester; c) at least one compound of formula(IIa):R₃OOC-A-CONR₄R₅  (IIa), wherein R₃ comprises a C₁-C₃₆ alkyl group;wherein R₄ and R₅ individually comprise a C₁-C₃₆ alkyl group, wherein R₄and R₅ can optionally together form a ring; and wherein A is a linear ora branched divalent C₂-C₆ alkyl group; d) at least onealkyldimethylamide; e) at least one alkyl lactate; f) ethyl levulinate;g) at least one alkyoxyalcohol, ether alcohol, amine alcohol, aminoalcohol or alcohol; h) at least one glycerine or glycerine derivative;or i) at least one alkylene carbonate; optionally fertilizer, wherein atleast one said fertilizer is a nitrogenous fertilizer; optionally water;optionally at least one dye; and optionally monoethanolamine as astabilizer, wherein the N-butyl thiophosphoric triamide or the mixtureof the N-butyl thiophosphoric triamide and the dicyandiamide is 0.5 to60 wt %, by total weight of the at least one inhibitor, theorganophosphate solvent, the dimethylsulfoxide, and, if present, theco-solvent.
 19. The composition of claim 18, consisting of N-butylthiophosphoric triamide as the urease inhibitor; the organophosphatesolvent of formula (VIII):

wherein R₁, R₂ and R₃, are each the C₂ alkyl group; thedimethylsulfoxide; optionally the fertilizer, wherein at least one saidfertilizer is a nitrogenous fertilizer; optionally the water; optionallythe at least one dye.
 20. The composition of claim 19, wherein N-butylthiophosphoric triamide is the at least one inhibitor, and triethylphosphate is the organophosphate solvent, wherein the N-butylthiophosphoric triamide is 40 to 60 wt %, by total weight of the atleast one inhibitor, the organophosphate solvent, and thedimethylsulfoxide.
 21. The composition of claim 18, wherein triethylphosphate is the organophosphate solvent, wherein the urease inhibitoris N-butyl thiophosphoric triamide and is 40 to 60 wt %, by total weightof the at least one inhibitor, the organophosphate solvent, and thedimethylsulfoxide, wherein for 100 parts by weight total N-butylthiophosphoric triamide, triethyl phosphate and dimethylsulfoxide thereis greater than 45 and up to 60 parts N-butyl thiophosphoric triamidewith a remainder of organophosphate solvent and dimethylsulfoxide,wherein the fertilizer, the water, and the at least one dye are presentin the composition.